Cameras using solid state image devices, such as charge-coupled devices (CCDs) and complimentary metal oxide semiconductor (CMOS) image sensors, have been rapidly distributed.
Pixel integration degree of the solid state image devices has increased so as to increase the resolution of the cameras. Also, the cameras have been rapidly made compact and light due to the improvement in performance of lens optical systems built in the cameras.
In a general lens optical system of a camera, a large number of lenses are used to secure a performance of the lens optical system, e.g., to secure a large angle of view and to correct aberration. Nevertheless, when the lens optical system includes many lenses, it is difficult to make the camera compact and light. Thus, there is a demand to develop a lens optical system that is compact, has a wide angle of view, and is easy to correct aberration.